In vitro assays with silencing and overexpression of MYBL2 and KDM5D in androgen receptor (AR)‐positive hormone‐sensitive prostate cancer cell lines, LNCaP and LAPC4, were used to assess their influence on cellular proliferation, apoptosis, and cell cycle distribution, as well as sensitivity to androgen deprivation, docetaxel, and cabazitaxel. Here, KDM5D is linked to Familial prostate cancer.